This invention relates generally to devices for assaying a condition in a human or animal such as pregnancy in a female which can be determined from body fluid such as urine and more particularly to a housing for such devices designed to control the flow of such body fluids on and across an enlarged exterior fluid sample receiving end of the housing, for establishing operative interrelation and engagement with an elongated test strip enclosed in the housing to control the quantity of the body fluid absorbed by the test strip, and for enhancing capillary flow along the test strip to a viewing window on the housing for viewing the positive or negative signal result on the test strip for the given test.
Single-use testing devices having a test strip therein for assaying a physical condition for humans and animals using body fluid, such as urine, by urinating thereon, by applying droplets of the body fluid thereon or by dipping the testing device in a quantity of the body fluid, are well known in the art, as is shown in pregnancy test devices of Abbott Laboratories covered by U.S. Pat. No. 5,075,078; of Carter-Wallace, Inc. covered by U.S. Pat. Nos. 5,739,041 and 6,046,057; and of Unilever covered by U.S. Pat. Nos. 5,602,040; 5,622,871 and 5,656,503; and also other U.S. Pat. Nos. 4,033,723; 4,123,224; 4,208,187; 4,774,192; 4,902,629; 5,173,261 and 5,356,782. These prior art patents show two basic types of pregnancy testing devices to which urine is applied. In one type the urine is applied to an exposed wick or specimen receiving end of the test strip. While good absorption of the fluid specimen is obtained by this type device, in order to achieve the desired operation and signal from the test strip, the device has many parts which increase the cost of assembly of these highly competitive products. In the other type of device the test strip is enclosed in the housing when the fluid sample is applied and flowed into the housing. Any unwanted hydraulic flooding which occurs produces improper and inaccurate signaling by the test strip on the result of a given test. Additionally, this second type of the test device also requires a plurality of parts and complex assembly which increases the cost per single-use device. Further, the prior art patents show that both of these type devices have relatively small impingement areas for the urine or fluid being tested and, as above indicated, pass high quantities of the fluid being tested into the housing for the respective test devices which produces unwanted hydraulic flooding and fluid pressures inside the test devices and tends to cause both improper chemical reactions and increased errors in the signals produced by and/or viewed in such testing devices.
The present invention overcomes these and other problems by providing a single-use testing device particularly adapted for detecting a physical condition such as pregnancy from a urine stream or specimen applied to the device in which a generally narrow elongated housing is particularly designed for holding and providing access to an elongated test strip disposed in the housing. The generally narrow elongated housing has an enlarged sample or specimen capturing or receiving area or section at one end which is shaped on the front surface and the rear surface of the housing with a plurality of serially disposed guide vanes with inlet ports or openings as hereinafter described disposed in their respective medial sections. The guide vanes and channels collect and pass the fluid to be tested which is brought into contact with or impinges on the enlarged specimen receiving section, through the medially disposed inlet openings, for contact and absorption by a test strip disposed along the longitudinal line in the housing and operatively disposed at one end for intimate engagement and coaction with the inlet openings in the enlarged specimen receiving end section of the housing. The inlet openings and the end of the test strip extending into the enlarged specimen receiving end section of the housing are operatively associated for engagement so that only a predetermined quantity of the fluid being tested is absorbed by the associated and coacting end of the test strip. The enlarged sized and shaped specimen receiving end section of the housing is further designed so that excess fluid to be tested or urine will overflow this end of the housing. The predetermined quantity of fluid or urine absorbed by the associated and coacting end of the test strip then travels by capillary action to a reaction portion on the test strip remote from the specimen receiving absorption end of the test strip, to a point for signaling the result, if any, of the physical condition on the given test. This signal can be detected through a window provided in the housing remote from the said enlarged specimen receiving end section on the housing. The housing is further designed with means to inhibit capillary action along joinder edges thereon to maintain the integrity of each test and has means therein to position, hold and protect the integrity of the test strip and to reduce excess moisture in the interior of the housing so as to insure proper directional capillary movement in the test strip of the fluid being tested and the accuracy of the test results.
It is another aspect of the present invention to provide a single-use testing device for detecting physical conditions from a fluid specimen or stream, such as urine applied thereto, having a housing movable from open to closed position to provide access to a test strip holding channel formed in and along the longitudinal line of the housing for holding an elongated test strip when the housing is in the closed position, said housing is enlarged, shaped and sized at one end to provide a specimen receiving area or section on the exterior of the housing for the fluid specimen or stream to be tested, an elongated handle section connected and continuous with one end of the enlarged specimen receiving end section has a sealed viewing window formed therein a spaced distance from the enlarged specimen receiving end section so that an elongated test strip, when mounted in the test strip holding channel, can extend from the enlarged specimen receiving end section through the housing past the viewing window, thus that the end of the elongated test strip in the enlarged specimen receiving end section can receive the sample quantity of the fluid specimen to be tested and transport the sample by capillary action past the viewing window in the handle, and the handle has venting means and desiccant means disposed relative the viewing window to prevent blurring of the window, collection of moisture and backflow of the sample so as to maintain the direction of capillary flow through the test strip when the test device is being used.
It is another aspect of the present invention to provide an improved structure and operation for a testing strip for use in a single-use testing device as above described consisting of an elongated multi-layered member sized to fit into a test strip holding channel formed on the housing for the testing device which has a base layer formed from a plastic film material on which a plurality of coacting and interrelated members or layers of absorbent and microporous materials are assembled and affixed to the base layer and/or to each other to provide a test strip having, an elongated sample collection end of highly absorbent material disposed when the test strip is in assembled position in the housing for operative engagement and coaction with the inlet ports or openings in the guide channels in the enlarged sized and shaped specimen receiving end section of the housing for easy absorption and saturation of a predetermined quantity of fluid or urine which is permitted to pass through the inlet ports or openings for contact with and absorption by the sample collection end of the test strip and for transport by capillary action of the absorbed fluid sample being tested to a reagent section for mixing a dried chemical reagent therein with the sample of the fluid specimen to be tested and to further transport this mixture to an intermediate section made of a microporous membrane which is in turn connected to an after-sol member made of a highly absorbent paper material. The intermediate section of the test strip extends past the sealed viewing window in the housing to signal the result of the test, if any, of the physical condition for which the test is being made and the after-sol pad continuous with the intermediate section further extends beyond the viewing window for communication with venting means and desiccant means in the housing to improve and maintain the proper directional capillary movement of the fluid being tested so the signal appearing in the viewing window will be accurate.
Thus, it is one aspect of the present invention to provide generally single-use testing devices for detecting physical conditions from a fluid specimen or stream such as urine applied thereto having, a housing movable from open to closed position to provide access to a test strip holding channel formed in the housing for holding a test strip made of absorbent and microporous materials when the housing is in the closed position, said housing is enlarged, shaped and sized at one end for receiving on the exterior of the housing the fluid specimen or stream to be tested, said enlarged specimen receiving end section has a plurality of serially disposed transverse guiding channels formed on at least one outer face of the housing. An inlet port or opening is formed medially in each of said transverse guiding channels and each of said plurality of inlet ports or openings is adapted for operative engagement and coaction with the sample collection end of the test strip mounted in the test strip holding channel to enable a predetermined quantity of fluid such as urine to be absorbed by to the sample collection end of the test strip. An overflow outlet on said enlarged end section is provided so that excess urine will flow off the enlarged specimen receiving end section of the housing, sealing means is formed along the joint closure line when the housing is in the closed position, including means to stop capillary action along the sealing means and prevent excess fluid or urine from entering the housing and contaminating the test strip in the strip holding space, and a sealed viewing window on said housing is provided for reading the reaction, if any, produced on the test strip from the absorbed fluid or urine sample being tested.
It is another aspect of the present invention to provide a test strip having absorbent and microporous materials for a single-use testing device in accordance with the present invention consisting of an elongated multi-layered member sized to fit into a test strip holding channel formed in the housing for the testing device which includes, a base layer formed from a plastic film material on which a plurality of additional members, elements or layers of absorbent and microporous materials are connected to the base layer and to each other in overlapping relation to provide an elongated sample collection member disposed for operative engagement and coaction in the enlarged specimen receiving end section in the housing to absorb and transport by capillary action a sample of the fluid to be tested, to a reagent section for mixing the dried testing chemical therein with the fluid sample to be tested and to pass it to one end of an intermediate microporous membrane extending through the housing connected at the opposite end to an after-sol absorbent pad, the intermediate microporous membrane which passes across the sealed viewing window to signal the result of the test, and the after-sol absorbent pad extends beyond the sealed viewing window for communication with the venting and desiccant means to enable the capillary action to continue through the test strip and insure that the signal provides an accurate reading in the viewing window for the fluid sample being tested.
It is another aspect of the present invention to provide a testing device having a housing with a lower shaped section and a coacting matching shaped upper section having means for generally sealing the upper and lower sections to each other to define a test strip receiving space therein when in the closed position and means on said housing to prevent capillary flow of fluid or urine contacting the outside of the housing along the means for sealing the upper section and lower section when in the closed position to increase the accuracy of the results obtained by the testing device and to prevent a person""s hands from being contaminated when urine impinges on the enlarged specimen receiving end section of the housing.
It is another aspect of the present invention to increase the accuracy of the results obtained by the testing device in accordance with the present invention by providing means to allow the fluid or urine impinging on the exterior of the test device to overflow without affecting the control of the predetermined quantity of fluid or urine which is absorbed by the coacting test strip in the housing.
It is another aspect of the present invention to provide vent means on the housing in communication with the interior to allow excess moisture to escape from the housing, prevent backflow of the fluid being tested along the test strip, to improve operation of the test strip therein, and also to prevent the viewing window from becoming blurred.
It is another aspect of the present invention to provide a desiccant in the housing to absorb moisture collected in the housing when the test device is not in use.
It is still another aspect of the present invention to provide in a testing device a test strip receiving channel, operative at one end to contain the test strip when placed therein for operative coaction with inlet openings or ports in the enlarged specimen receiving end section to control the quantity of fluid to be tested which is absorbed by the operatively engaging and coacting sample receiving end of the test strip in engagement with the inlet ports or openings in such assembled position, to prevent fluid from entering the housing, and to easily establish and continue movement of the fluid being tested by enabling the capillary action to continue when the test device is in use.
It is a further aspect of the present invention to provide in a testing device a longitudinally extending test strip receiving channel in and along the housing for removably receiving an elongated test strip therein which extends from the enlarged specimen receiving end section past the viewing window and for contact with protruding members on the inner wall of the housing for holding the test strip in assembled position in the test strip receiving channel.
It is a still further aspect of the present invention to provide in a testing device having a housing with an enlarged specimen receiving section at one end for contact with a fluid to be tested such as urine, guide channels and inlet ports for the fluid to be tested, on said enlarged specimen receiving end section, a viewing window remote from the enlarged specimen receiving end section for signaling the results of the test of such fluid, venting openings on the side of said window viewing section opposite from the enlarged specimen receiving end section, and a longitudinally extending test strip receiving channel in and along the longitudinal line of the housing for receiving an elongated test strip made of absorbent and microporous materials in operative engagement at one end with the inlet ports in said enlarged end section to control by the absorption as a function of the materials the quantity of fluid to be tested and the opposite end of said test strip extending beyond the viewing window to enable absorbed fluid being tested to vaporize through vent openings in the housing so movement by capillary action of the absorbed fluid in the test strip is maintained and will continue, and backflow of absorbed fluid in the test strip is prevented. While the test strip has an operative interrelation with the inlet ports or central openings in the guide channels of the enlarged end sections, those skilled in the art will recognize that such test strips are well known to those skilled in the art.